The electrical transport through self-assembled monolayers of alkanedithiols was studied in large-area molecular junctions and described by the Simmons model [Simmons JG (1963) J Appl Phys 34:1793-1803 and 2581-2590] for tunneling through a practical barrier, i.e., a rectangular barrier with the image potential included. The strength of the image potential depends on the value of the dielectric constant. A value of 2.1 was determined from impedance measurements. The large and well defined areas of these molecular junctions allow for a simultaneous study of the capacitance and the tunneling current under operational conditions. Electrical transport for octanedithiol through tetradecanedithiol self-assembled monolayers up to 1 V can simultaneously be described by a single effective mass and a barrier height. There is no need for additional fit constants. The barrier heights are in the order of 4 -5 eV and vary systematically with the length of the molecules. Irrespective of the length of the molecules, an effective mass of 0.28 was determined, which is in excellent agreement with theoretical predictions. and consist of a saturated carbon backbone with one (or two) thiol end groups. Experimentally, the tunneling current through a monolayer of alkane(di)thiols was shown to be temperatureindependent and to decrease exponentially with increasing molecular length (4, 5). The transport has been interpreted in terms of the classical tunneling model through a thin insulating film as provided by Simmons (24,25). In this model the tunneling current depends on the mean value of the barrier height, allowing for a simplification of the problem of an arbitrarily shaped potential barrier to that of a rectangular barrier. This model has been applied to junctions based on SAMs (4, 26), but an extra fit parameter ␣ is needed to obtain a fit to the measured data. However, as already explained by Simmons (24, 25), for a practical tunnel junction the image potential has to be taken into account. This effect has been neglected in the literature so far.The system studied in this article is a tunnel junction with an alkanedithiol SAM as the insulating film, a bottom gold electrode, and a highly conducting polymer as a top contact. The polymeric top contact allows for the fabrication of devices with a yield of almost unity for areas up to 100 m in diameter (5). The highly conducting polymer used is PEDOT:PSS, a waterbased suspension of poly(3,4-ethylenedioxythiophene) stabilized with poly(4-styrenesulfonic acid). The polymer acts as a cushion for the thermally evaporated metal atoms to land on and prevents the metal atoms from penetration into the molecular layer. Consequently, the formation of electrical shorts is prevented (27). Simmons ModelThe tunneling current density J through a rectangular potential barrier with height 0 is given by (4, 24, 26):wherewhere ⌬s is the barrier width at the Fermi level of the electrodes, here equal to the total length s of the tunneling path between the electrodes, m e is the bare electron mass, V is th...

An overview of the merits and applications of batch ALD in a vertical furnace will be presented. We address new material and process developments and throughput enhancement which are key factors for future high-volume manufacturing applications. We present ALD SbOx as a new material on the batch platform. For the workhorse ALD Al2O3 and TiN materials, experimental and simulation results demonstrate that a reduction in cycle time to <21s does not significantly compromise uniformity, resistivity and step coverage. Moreover, batch ALD offers process flexibility in the mitigation of non-idealities, such as growth inhibition, as will be discussed for thermal ALD AlN. The very low non-uniformities < 1% (1σ) for the latter process demonstrate the competitive film properties that can be achieved by batch ALD. With applications as diverse as metal gates in logic, trench capacitor electrodes, capacitor dielectrics, barrier layers and passivation films, batch ALD has firmly established itself at device manufacturers and foundry sites with significant prospects for emerging markets.

This work reports the feasibility of silicon and silicon germanium epitaxy using an ASM A412(TMa) LPCVD all quartz, hot wall, vertical batch furnace reactor using 100 wafer product loads. The very same furnace can be used for 25 wafer and 200 wafer load size, without any hardware changes, dependant on production needs. Following this approach a significant cost reduction for epitaxy in 300 mm high volume manufacturing is possible and enables new applications. The native oxide of the substrate was removed by wet chemical cleaning with time coupling of less than 1 h and subsequent in-situ low pressure hydrogen anneal prior to Si or SiGe deposition. The epitaxial layers were grown using silane and germane. The Si and SiGe layers have been characterized with ToFSIMS, XRD, Raman, AFM and TEM confirming excellent crystalline quality, layer thickness and within wafer SiGe stoichiometry uniformity.

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